Sheave-block mounting



Aug. 16, 1938. R. G. LE TOURNEAU 2,127,034

'SHEAVE BLOCK MOUNTING Filed Jan. '7, 1958 l I INVENTOR RQGILeTOurN/eaw Patented Aug. 16, 1938 UNITED STATES-1 SHEAVE-BLOCK MOUNTING- Bobert Gilmore Le Tourneau, Peoria, 111., assignor to R. G. Le Tourneau, Inc., a corporation of California Application January 'l, 1938,' Serial No. 183,820

3 Claims.

This invention relates to the mounting of sheave blocks on movable cable controlled booms and the like, under operating conditions where such sheave blocks are apt to be drawn quite close to the relatively fixed cooperating sheave blocks about which the cables pass.

An arrangement of parts, calling for such relative movement of the sheave blocks, is shown, for instance, in my Patent No. 1,875,047 dated August 30, 1932, as well as in the scraper shown in my copending application for patent Serial No. 179,481, filed December 13, 1937.

When the sheave blocks are fixed on their respective parts in such positions that the pulleys are in permanent parallel alined relation, the cable runs extending between such pulleys are unduly angled when the pulleys are close to each other and tend to bind and wear excessively, or jump the pulleys.

This can, of course, be overcome by the use of sheave blocks mounted with eye or similar universal connections,'but such arrangements are not suitable for the kind of implement and the type of construction which I employ.

It is therefore the principal object of my invention to provide what I believe to be a novel form of sheave block mounting which will permit of the movement of the sheave block about a definite circular path, and also allow the same to oscillate or swing in a lateral plane so as to cause the pulleys of the sheave block to properly aline with .corresponding ones of the fixed block when said blocks are close to each other.

A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawing similar characters of reference indicate corresponding parts in the several views:

Figure 1 is a fragmentary side outline of a tractor mounted scraper according to said Patent No. 1,875,047, equipped with my improved sheave block mounting.

Figure 2 is a top plan view of the movable sheave block showing the novel mounting thereof.

Figure 3 is a diagrammatic plan showing the two sheave blocks in widely separated relation, and illustrating the relatively sharp angular relation of the cable runs when the pulleys are close and if the movable block was rigidly mounted.

Figure 4 is a diagrammatic end view of the pulleys of the two blocks in adjacent relationship, and with the movableblock mounted according to my invention.

Referring now more particularly to the char- 5 acters of reference on the drawing, the structure herein shown to illustrate the use of my sheave block mounting comprises side arms I supporting a scraper bowl 2 at one end and pivoted at the other end as at I in a relatively 1o fixed position.

Secured on a fixed framework F at a certain height above the pivot 3 is a sheave block 4 including pulleys 5. Secured on the bowl 2 at the back and adjacent the top are transversely 15 spaced ears 6, which support a pin 1 extending therebetween. Disposed just above or beyond the ears is another sheave block 8 including pulley 9. A single ear It is secured rigid with the back of the block 0 and projects between 20 the ears 6 in spaced relation thereto. This ear I0 is provided with a circular hole ll considerably larger than pin I and through which hole the pin passes. A filler element l2, having a straight chordal face parallel to and opposite 25 the back of the sheave, is secured in the portion of the hole beyond the portion thereof required for the pin, or so that a line drawn through the center of the hole at right angles to and extending from said chordal face to the opposite 30 edge of the hole, will be equal in length to the diameter of the pin. The pin is thus held be-' tween diametrally opposed points only, and the sheave -block can turn about the pin as an axis without any lost motion, providing for smooth 35 running operation and a minimum of wear. The block can also rock laterally on the pin a limited amount to one side or the other.

The actuating or control cable ll, which passes backand forth between the pulleys of the two sheaves, crosses over on one run as usual from a pulley of one block to an adjacent laterally offset pulley of the other sheave, as indicated in Fig. 3. Thus, when the pulleys of the two blocks approach each other, this cross over would be quite abrupt if it were not for the swivel mounting of the block 8. At it is, the block 8 can swivel laterally as shown in Fig. 4, so as to equal- 1y divide the angular relationship of the cable 50 runs on opposite sides of the pulleys, reducing cable wear and the tendency to jump the pulleys to a minimum.

From the foregoing description it will be readily seen that I-have produced such a device as u substantially i'ulfills the objects or the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction or the device,

still in practice such deviations i'rom such detail may he resorted to as do not form a departure from the spirit or the invention, as defined by the appended claims. 7

Having thus described my invention, what I claimasnewanduseiulanddesiretosecure l. A sheave-block mounting comprising a re]- ativeiy thin ear rigid with and projecting from the hack of the block. said ear having an initially circular hole therethrough whose axis is parallel to that oi the sheaves oi the block, a fixed round pin or smaller diameter than the hole projecting therethrough, and an element secured in and partially filling the hole and engaging the pin onone side only while maintaining the pin at a ofpull on the block,-and is on the side oi the pin farthest from said block.

ROBERT G. LE TDURNEAU. 

